Surviving the Sharpshooter

Southern California's Vineyards Hang On 

Wine Spectator 15sep01

Despite the devastation wrought by the carrier of Pierce's disease, optimism reigns in Temecula.

Driving through the Temecula Valley in southern California this spring and summer, you'd hardly guess anything was wrong at all. The wine region appears prosperous, vines look lush and green, and tourists are out in full force. Local growers are busily replanting their vineyards, and some are even expanding. One new winery is under construction, and two are being upgraded by new owners.

Yet gaping holes in the rows of vines are evidence that the voracious pest known as the glassy-winged sharpshooter has been having a field day in Temecula.

The tiny appellation, which has only about 2,500 acres of grapevines, was devastated after the glassy-winged sharpshooter, an insect native to the southeastern United States, moved into the valley and rapidly spread the bacterium responsible for Pierce's disease, a fatal vine malady. The problem was first identified in the region in 1997, and by 1999, the insects and the disease were rampant. To date, about 840 acres of vines have died or been ripped out.

"In one season, I saw 30 percent of my vineyard collapse," said Peter Poole, owner of Mount Palomar Winery. As if that weren't bad enough, he added, "early this year, a new threat appeared and that is the rumor that our region was finished."

The glassy-winged sharpshooter has spread quickly to other parts of the state, probably transported on ornamental plants shipped by nurseries. There are now six "generally infested" counties in southern California, and another nine "partially infested" counties, including Santa Clara, where an infestation was found in San Jose this July. Many in the wine industry fear that if pesticides are not used to control its spread, the insect could reach Napa and Sonoma and cause similar devastation there.

Although Temecula is ground zero for Pierce's disease, most of the region's . growers are now expressing guarded or wholehearted optimism about the valley's future.

Among those making new investments is Ray Falkner, who opened Falkner Winery fully aware of the Pierce's disease threat hanging over the region. He and his wife, Loretta, purchased Temecula Crest Winery in June 2000, even after a survey of its vineyards that spring found that up to 20 percent of the vines were infected. Nonetheless, the couple is expanding annual production from 6,000 cases to 15,000 cases and building a new 10,000 square-foot winery facility.

"This makes us either the most stupid people around, or the most optimistic," said Falkner. "I am very familiar with what it takes to get a business off the ground, and after careful consideration of the information at hand, Loretta and I decided to go for it. Many times, adversity and opportunity are flip sides of the same coin."

Where's the opportunity in a situation this dire? Although Pierce's disease has existed in California since the late 1800s, "for the first time in the state's history, top scientists in several fields and some of the best people in the wine industry are setting their minds to solve the problem," said Poole. Government and wine industry sources have contributed $39.2 million in funds since 1999 to combat the glassy-winged sharpshooter and Pierce's disease. And another bill to raise millions was signed by Gov. Gray Davis in July.

Since 1999, Temecula growers have learned lessons from which vintners in the rest of California may benefit. They have embarked on an aggressive campaign of spraying pesticides and insecticides, ripped out nearby citrus groves where the insects winter and lay their eggs, removed infected vines on which the insects could feed and then further spread the disease, and replanted with more resistant varieties. The end result: a significant reduction in the number of glassy-winged sharpshooters.

"I have been to Temecula and can attest to the fact that, a year ago, you could walk up to a vine and find sharpshooters without looking very hard at all," said Jay Van Rein, a spokesman at the California Department of Food and Agriculture. "This summer, you'd have a hard time finding any without a good, long search."

Temecula has been fortunate enough to be able to buy time in its fight, while researchers study other solutions ranging from organic treatments of kaolin, which inhibits sharpshooter feeding, to genetically altered vines. (Researchers at the University of Florida recently developed a genetic engineering technique that appears to give vines resistance to Pierce's disease, but the method has only been tested on Thompson Seedless vines.)

Temecula had a large crop in 2000--with yields as much as 25 percent to 30 percent greater than in 1999sparing wineries the financial burden of buying grapes from elsewhere or cutting production.

But the valley's largest Producer, Callaway Vineyards and Winery, has begun purchasing additional grapes from other sources, including Central Coast vineyards in Santa Barbara and Monterey counties. Callaway was particularly hard hit-close to 40 percent of its vines are now gone--because its vineyards are heavily planted with highly Pierce's disease-susceptible Chardonnay and Sauvignon Blanc.

Last summer, the company changed its brand name to Callaway Coastal, reflecting the change in grape sources. That move has been interpreted by some in Temecula as Callaway's attempt to disassociate itself from the region's problems. But spokeswoman Peggy Evans said that the winery is purchasing grapes from outside Temecula so it can expand production to 1 million cases.

Temecula's future is still uncertain, and no one is quite sure how many more acres of vineyards are infected. An August 2000 survey found an average of over half the vines were infected, said Matthew Blua, a research entomologist at the University of California at Riverside. He noted that some of those vines could have recovered if the disease was limited to a part of the plant that can be pruned off.

Although Temecula's remaining vines may look healthy now, said Blua, the symptoms of Pierce's disease become increasingly apparent in mid-August through mid-September. Still, with the reduction in the number of sharpshooters, Blua is cautiously optimistic about Temecula's ability to survive.

None of Temecula's growers seem interested in giving up yet. Carol and Phil Baily, who own Baily Winery, have invested a little the over $1 million in a new wine production facility and equipment since the Pierce's outbreak, in addition to their recently opened $1 .2 million visitor center.

"We never really expected to go out of business," said Carol Baily. "There's always some new threat looming on the horizon when you're in agriculture- You don't just roll over and die; you find ways to cope with it."

Article by Lynn Alley, with additional reporting by Daniel Sogg